Chisel



(No Modell.)l I

0.12.. BOSTIAN.

- GHISEL. Y 10.420,529. 'Patented Feb. 4.1890.

UNITED STATES "PATENTA OFFICE.'

4CHARLES P. Bos'rIAN, oF MILTON, AssIeNoR oF ONF-HALF To JoHN F.

MFcKLFY, oF wA'rsoN'rowN, PENNSYLVANIA.

CH ls EL.

SPECIFICATION forming part of Letters Patent No. 420,529, dated February 4, 1890.

' Apigiic'aio'nica september 19,1889. 'serial No. 324,401. (No model.)

1 To all whom it may'colwern:

Be it known that I, CHARLES P. BosrIAN, a citizen of the United States of America, residing at Milton, in the county of Northumberland and State of Pennsylvania, have invented certain new and useful Improvements in Chisels, of which the following is a'speciiication. Y

My invention has relation to improvements in chisels; and the object is to provide an implement or tool adapted to mortising and having the characteristic or functionsof cleaning the mortise of the chips made during the operation of cutting the mortise.

My inventionv therefore consists in a chisel of the particular construction hereinafter specified, and especially as the same is particularly pointed out in theclaims.

I have fully and clearly illustrated my invention in the accompanying drawings, where- 1n- Figure l is a view of the complete chisel. Fig. 2 is a view of the stock with the chiselbit removed. Fig. 3 is a view of the chiselbit removed from the stock. Fig. 4 is a view of the chip-clearer removed from the chisel. Fig. 5 is a View of a modiiied means for securing the bit to the stock. Fig. 6 is a detail of the stock of the4 chisel shown in Fig. 5. Fig. 7 is a detail of the bit of the chisel shown in Fig. 5. Fig. 8 is a view showing the chipclearer attached to an integral stock and chisel.

' A designatesl the stock, having parallel sidel faces, a straight back face, and inclined on the front face for a distance extending to the bit end, as seen at l. At the lower end of the stock-piece in therear face the metal is cut away, forming a seat 2 to receive the shank of the chisel-bit. At the upper end of this seat 2 is formed a transversely-arranged dovetail groove 3, to take the dovetail projection or lug on the end of the shank of the chiselbit. The projecting wall, as 4, of this groove is chamtered oit on its side edges, as at 5, making the endnarrower and somewhat tapered to engage the socket formed in the inclined end of the shank ofthe chisel-bit, and thus h old that element against displacement laterally. The lower wall of the dovetail may be arranged at a slight incline across the stock, in order to have a wedging function to the bit.

when the key is inserted. The metal of the stock is extended at the sides below the end, as seen at 6, and in these extensions are formed small notches 7, constituting the bearings for the bearing-lugs on the hinged chipcleaner. The extensions have inclined ends, as shown, to set against the oppositely-arranged inclines on the. chisel-bit.

B designates the chisel-bit, having a shank formed with a seat S to rest on the floor of the seat 2 in the stock. The upper end of the seat 8 terminates in a dovetail lug 9, the end face of the shank being formed at an incline, with the sides extended, as seen at 10, to t over and against the formed upper wall of the dovetail groove in the stock. The lug 9 is made shorter than the width of the groove across the stock, in order that when the parts are laid together there willbe formed a key-space between them, in which a key 11 is driven, and the stock and bit thus firmly locked together. The bit is formed with side bits 12 on its edges to cut in advance of the chisel-bit and break the chips, so that the progress of the tool will be aided, and in the center of the bit may be a line of teeth l2xto aid in breaking the chips. The upper end of the bit terminates in a projecting incline wall 13, against. which the end of the stock sets and is held.

O designates the chip-cleaner. This consists of a piece of metal having points lll on its free end, and formed with bearing-lugs 15 to fit in the bearings on the stock. rlhis chipcleaner is arranged in its bearings so that it may turn up out of the way when the chisel `is driven into the wood and to turn down and fied means for connecting the stock and bit,

which consists in making the shank of the bit tit a seat in the end of the stock and projecting a screw through them. The clearer or cleaner is also mounted on a'bearing-pin, and forms in this respect a permanent connection It will thus be seen that the use of the hinged clearer is not conned to the chisels having detachable bits, but may be hinged to an integral tool and serve the purpose intended. The instrument isadapted for use in any mortising-machine, or a han- IOO dle may be put on the stock and used as a hand-chisel in the usual Way.

The operation is apparent. The tool having entered the wood below the surface to any depth in the progress f cutting mortises, the chips made are drawn out bythe hinged chippieee when the chisel is Withdrawn.

I am aware that mortising-chisels have been made with side edges to cut in advance of the bit; but I believe I am the first in the art to provide a chisel with a cleaning-piece hinged to the face of the chisel and arranged to operate as described, and to this end it is apparent that the bit and shank may be integral and -the chippiece hinged to the face, as more fully mentioned hereinbefore.

. Having thus described my invention,Ipro ceed to particularly point out and distinctly claim what I claim as my invention, as follows:

1. A mortising-chisel provided with a chippiece hinged to the front face of the bit and arranged to normally lie vertically against the face of the bit and to turn down and lodge at right angles to the bit when the chiselis lifted in the inortise, substantially as described.

2. A inortise-chisel provided with a cleaning-piece hinged to the front face of the bit and formed with a notched edge and arranged to lie against the face and to turn down and lodge at right angles thereto, substantially as described.

3. The mortising-chisel composed of ast-ook A, formed with a seat at its lower end to receive the shank of the chisel-bit and provided with a chip-piece hinged to its front face, a chisel-bit having a shank to engage the seat in the stock, and fastening means projected through the stock and the shank of the chiselbit, all substantially as and for the purpose specified.

4. The nrortising-chisel composed of a stock A, formed with a seat 2 at its lower end, having a dovetail groove 3 across the upperportion and bearing-notches 7 at its lower end,a chisel-bit l0, having a shank to set on the seat of the stock and formed with a dovetail lug to engage the dovetail groove of the stock, a hinged chipcleaner C, having its journals in the bearings ol the stock, and a key to lock the stock and bit together, substantially as described.

In Witness whereof I have hereunto set my hand in the presence of two attesting witf nesses.

CHARLES I. BOSTIAN.

Attest:

JOHN F. MECKLY, Jos. ANGs'rADT. 

